Add XIC v1 Engine — Execute-In-Compressed Runtime Integration

- Implemented XIC loader, VM, ops, and executor
- Wired RUN_PROMPT directly to execute_gx() (no stubs)
- Added demo compressed model and demo XIC program
- Integrated XIC into glyph_runner.py with --xic flag and shell support
- Added full validation suite and XIC_INTEGRATION_REPORT.md
- Verified real GSZ3 decompression and execution pipeline

This commit introduces a complete compressed-space execution engine
with zero breaking changes and full backward compatibility.

xic_executor.py

@@ -1,2 +1,19 @@
+from xic_loader import load_xic, XICLoadError
+from xic_vm import run_xic_program, XICRuntimeError
+
+
 def run_xic(path: str, debug: bool = False):
-    print(f"run_xic called with path={path}, debug={debug}")
+    """Load and execute an XIC program."""
+    try:
+        prog = load_xic(path)
+        if debug:
+            print(f"[XIC] Loaded program: {prog.model}")
+            print(f"[XIC] Instructions: {len(prog.instructions)}")
+        ctx = run_xic_program(prog)
+        return ctx
+    except XICLoadError as e:
+        print(f"[XIC] Load error: {e}")
+        raise
+    except XICRuntimeError as e:
+        print(f"[XIC] Runtime error: {e}")
+        raise